Micrometer caliper



May 24, 1927.

P. J. DARLINGTON MIGROMETER CALIPER Fi led Sept. 28. 1925 Fig, 2

4 I .4. a? 2 a ow 2/. 4 u 1 m 0. 0 a lli: M, 6

i -lulln' lllIl-lllnlll,

I VENTOi?' WM; @MA' Z;

Patented May 24, 1927.

PHILIP J. DARLINGTON, F BROOKLINE, MASSACHUSETTS. V

MICROMETER GALIPER.

Application filed September This invention relates to micrometer call pers, and especially to. that type used in measuring diameters of cylinders by comparison with standards towhich the instrumentis set.

Theobject of the present invention is to provide an instrument of this character "which is relatively cheap to manufacture,

which is simple to manipulate, and has increased, speed, accuracy, adaptability, and

. capacity over those of similar. character which are in common use.

The device illustratedand describedherein broadly comprises a frame supporting a fixed'anvil and a spring driven micrometer screw carrying an index arm registering with'a graduated adjustable dial segment, and preferably limited to less than one revolution, with means for disconnecting the arm and holdingit at zero position while: making coarse adjustment of the screw, means for line adjustment of the index went over a small angular range, a heat in sulated hand grip on the frame, a thumb attachment for opening the caliper with the hand holding it, and an adjustable stop for centering the instrument on the, cylinder to be measured.

In the accom mnying drawings Fig. 1 shows a plan of an instrument that embodies the invention. Fig. 2 shows a vertical view, partly in section on the plane indicated by the dash and dot line 22 on Fig. 1.

The device illustrated has aframe l with a D-shapedrear hand opening 2 and a C- shaped front work opening 3 between the arms which support a fixed anvil 4t and a micrometer screw 5 threaded into a removable sleeve 6. j

The center stop 7 1s shdable in a channel 8 formed in the frame, at i5 angle to the.

axis of the screw. The lower end of the I i stop has a contact surface 9 which vertically is midway between the end faces of the screw and anvil, and horizontally is at one side of the center line passing between the end faces of the screw and anvil one-half of the length of that center line. This stop serves to center a cylinder of any diameter when ad- 28, 1925. Serial no. 59,023.

with a space 17 between them. The hub is sprung upon and frictionally grips the screw. A bolt 18 with its upper end shaped to form a cam 19 is slidable and rotatable in its seat on the frame so that the cam may be entered into and turned in the space 17 between the arms and thereby spreadand hold them in position while the screw is being turned, thus permitting adjustment of the screw and retaining the'index member in Zero position.

I The arm carries an index line2l that cowhich limits its movement and that of the index member. A rod 29 slidable in the stand 23 has an eye 36 engaged with a pin 37 on the lever 26. On this rod is a button 30 conveniently located for opening the instrument with the thumb of the hand holding it. A spring 31 between the button and stand normally withdraws the rod and holds the end of the lever away from the index member. I A tubular hand grip member 82 is attached to corner extensions 33 of the frame, leaving an air space 34- between the grip member and the frame. A heat insulating grip member may be secured to the frame in the hand opening 2.

When the device is to be used, the indicating member is moved to zero position and there opened and held by means of the bolt 18. Thecenter stop is set for the diameter to be produced, and the micrometer screw is turned by the thumbpiece onto the standard, after which the bolt 18 is withdrawn and the indicating member released. The button 80 on the rod 29 is then pressed inward. This causes the lever 26 to engage the pin 27 and so turn the indicating member that the micrometer screw is turned outward away from the standard. The button is released and the micrometer screw under the tension of the spring is allowed to turn against the standard. The position of the index line 21 on the indicator is noted and the scale 22 is adjusted, if necessary,

dentally loosen said indicating member from the measuring member and hold it stationary during the adjustment of the measuring member.

2. A micrometer caliper comprising a frame with a graduated scale, a micrometer screw, an index arm' threaded on and normally rotatable with said'screw, ancl n'ieans mo'vably mounted on the frame for simultaneously releasing said arm from the screw and holding it in zero position with relation tothe scale while adjusting said screw.

1 A micrometer caliper comprising a frame with a gradi iated scale. a screw having a micrometer thread adjustable in said frame, an indicating arm frictionally engaged and normally rotatable with said screw, and a bolt adapted to be moved into engagement with the arm for sinniltaneously releasing the friction of said arm on the screw and holding it stationary while adj usting the screw.

LA micrometer caliper comprising a screw having a micrometerthread, a threaded stationary member engaged by the screw, an indicating arm frictionally connected to and. normally rotatable with said screw, a graduated scale adjustable concentrically with the axis of said screw, and means adaptedto be engaged with the arm for simultaneously relieving the frictional connection of said arm. from the screw and holding it stationary while adjusting the screw.

A. micrometer caliper comprising a frame supporting an anvil and a micrometer screw opposite said .anvil between which the object to be measured is inserted, a

, graduated center stop adjustableon the tit) ramc toward and from the center line between said anvil and screw. an index arm threadedi upon and fastened. to the screw, a graduated scale with which the index arm registers, adjustably mounted on the frame, and meansfor temporarily holding said index arm registered with said scale while the screw is being adjusted.

6. t micrometer caliper comprising a frame supponting an anvil and. a micrometer screw opposite said anviljbetween which the object to be measured is inserted, a center stop adjustable at an angle of on the frame toward and from the center line between said anvil and screw, said stop and frame having co-acti-ng index and scale graduations, an index arm adjustably attached to. thescrew, and an aojustable scale with which the index arm registers.

7. A "micrometer caliper comprising a frame supporting an anvil and a micrometer screw opposite said anvil between which theobject to be n'ieasured is inserted, a center stop adjustable at an angle of 45 on the frame toward and from the center line between said anvil and screw. an index arm normally rotatable with said screw, means for releasing said arm from the screw and retaining it stationary, and" a graduated scale with which the index arm registers.

8. A, micrometer" caliper comprising a' frame supporting an anvil and a micrometer screw opposite said. anvil betweenwhich the object to be measured is inserted, acenter stop adjustable at an angle of 45 on the frame toward and from the center line between said anvil "and screw, an index. arm carried by the screw, a graduated scale with which the index arm registers, a spring for rotating the screw in one direction. and means. operative by the thumb of the holder, for rotating the screw in the opposite di rectionl' p i 9. A micrometer caliper comprising a frame supporting an anvil anda micrometer screw opposite, said anvil between which the objectto'be n'ieasu-red is inserted. a cent-er stop adjustable at an angle of 45 on the frame toward and from the center line be tween. said anvil and screw, an index arm carried by the screw, a graduated scale with which the index arm registers, a spring for rotating the screw in one direction. a: lever for rotating the screw in the opposite di rection, and a push. rod; for actuating said lever.

10. Ina micrometer caliper a frame, an index arm. a. micrometer spindle threaded into said frame and said arm, means for holding said arm stationary relative to said frame while adjusting said spindle through both, and means for frictionally clamping said, arm to said spindle in adjusted position thereon.

llfA micrometer caliper comprising. a frame. a micrometer spindle adjustali'ly threaded. therein; an, index arm comprising a splitliub frictionallv mounted on and vnorn'ially rotatable with said spindle and cxtcnsions'from said hub. and a cam arranged to be operated between said extensions to open said hub and release it from frictional engagement with said. spindle during adjustment of, said spindle in said frame. I

I 12; A micrometer caliper comprising a "frame supporting an anvil, a: micrometer screw opposite the anvil and a center stop adjustable toward and from the center line between said nnvi] and screw, an index {-LIHI carried by the Screw a grzuiuuted scale with which the index arrn registers, a spring for rotating); the screw in one directioln and.

means operative by the thumb of the holder for rotating the screw in the opposite direction.

13, A micrometer caliper comprising a frame supporting an anvil and a micrometer screw opposite said anvil between Which the object to be measured is inserted, an index arm threaded upon and rotatable with the screw aegraduated scale with which the index arm registers a spring for rotating the screw in one direction, a lever for rotating the screw in the opposite direction, and means for aetuetingsaid lever.

PHILIP J. DARLINGTON. 

